It’s been a rough three years for Michael Douglas and Catherine Zeta-Jones. Between his cancer diagnosis and her repeated treatment for bipolar II disorder, they have been through enough to test even the strongest of bonds. Now, sources close to the couple say they’re taking a break — from each other.

A pal explained succinctly why Douglas is sunning himself on a yacht off the coast of Sardinia while Zeta-Jones stayed behind at their home in New York.

“They’re taking a break,” the insider told People. “The stress has taken a toll on their marriage.”

Friends say it’s just a temporary time-out for now, and neither Douglas nor Zeta-Jones has made a move to file for legal separation or divorce.

“True love takes work,” he told The Mirror in July. “Love is an extraordinary feeling that comes from the bottom of your soul, but has to be nurtured, you know. The thing I’ve learned about getting older is you can’t take love for granted. You protect it, nurture it and it grows, and after one’s initial, physical, emotional aspects, it becomes deeper.”

She recently told the Sunday Telegraph that “respect, space and a sense of humor,” are the keys to a happy marriage. “We spend a hell of a lot of time together, so we are careful to maintain our space.”

“Given the age difference [he is 68 and she 43], what’s remarkable is that we are so similar in so many ways. We have a laid-back, easygoing relationship.”

Regardless of the outcome, one thing is for certain. “They want the best for their kids, no matter what happens,” a friend told People.

UPDATE: A rep for the couple has confirmed the split, saying in a press statement, “Catherine and Michael are taking some time apart to evaluate and work on their marriage. There will be no further comment.”